diff options
Diffstat (limited to 'src/kernel/mem/gdt.c')
| -rw-r--r-- | src/kernel/mem/gdt.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/src/kernel/mem/gdt.c b/src/kernel/mem/gdt.c index 5aaad41..18a5fa7 100644 --- a/src/kernel/mem/gdt.c +++ b/src/kernel/mem/gdt.c @@ -3,12 +3,18 @@ #include <core/monitor.h> extern void gdt_flush(uint32_t); //ASM (idt_.asm) +extern void tss_flush(); -#define GDT_ENTRIES 5 +#define GDT_ENTRIES 6 +static struct tss_entry tss_entry; static struct gdt_entry gdt_entries[GDT_ENTRIES]; static struct gdt_ptr gdt_ptr; +void gdt_setKernelStack(uint32_t esp0) { + tss_entry.esp0 = esp0; +} + static void gdt_setGate(int num, uint32_t base, uint32_t limit, uint8_t access, uint8_t gran) { gdt_entries[num].base_low = (base & 0xFFFF); gdt_entries[num].base_middle = (base >> 16) & 0xFF; @@ -20,6 +26,20 @@ static void gdt_setGate(int num, uint32_t base, uint32_t limit, uint8_t access, gdt_entries[num].access = access; } +static void gdt_writeTss(int num, uint32_t ss0, uint32_t esp0) { + uint32_t base = (uint32_t)&tss_entry; + uint32_t limit = base + sizeof(struct tss_entry); + + gdt_setGate(num, base, limit, 0xE9, 0); + + memset(&tss_entry, 0, sizeof(struct tss_entry)); + + tss_entry.ss0 = ss0; tss_entry.esp0 = esp0; + + tss_entry.cs = 0x0b; + tss_entry.ss = tss_entry.ds = tss_entry.es = tss_entry.fs = tss_entry.gs = 0x13; +} + void gdt_init() { gdt_ptr.limit = (sizeof(struct gdt_entry) * GDT_ENTRIES) - 1; gdt_ptr.base = (uint32_t)&gdt_entries; @@ -29,8 +49,10 @@ void gdt_init() { gdt_setGate(2, 0, 0xFFFFFFFF, 0x92, 0xCF); //Kernel data segment gdt_setGate(3, 0, 0xFFFFFFFF, 0xFA, 0xCF); //User code segment gdt_setGate(4, 0, 0xFFFFFFFF, 0xF2, 0xCF); //User data segment + gdt_writeTss(5, 0x10, 0); gdt_flush((uint32_t)&gdt_ptr); + tss_flush(); monitor_write("GDT ok\n"); } |